# Table 21: Robustness Matrix -- Z_1 on Inflation

Each cell reports the key demographic coefficient (SE) with significance stars (* p<0.1, ** p<0.05, *** p<0.01).

| Specification | Full | OECD | Pre-GFC | Post-GFC | Low inc | Mid inc | High inc |
|---|---|---|---|---|---|---|---|
| 1. Baseline | -12.842 (14.193) | -17.335 (14.917) | -10.232 (18.013) | -1.029 (17.186) | -- | -- | -12.842 (14.193) |
| 2. Alt demographics | 25.932 (61.018) | 8.346 (61.493) | 401.304*** (154.390) | -73.589 (53.296) | -- | -- | 25.932 (61.018) |
| 3. 5-year lag | -0.683 (11.441) | -1.874 (11.813) | -28.097** (13.750) | 31.527* (17.342) | -- | -- | -0.683 (11.441) |
| 4. First differences | -146.239** (58.050) | -143.561** (61.240) | 116.633 (77.905) | -362.422*** (82.947) | -- | -- | -146.239** (58.050) |
| 5. + Investment/GDP | -13.371 (14.211) | -17.258 (14.986) | -10.697 (17.984) | -2.125 (17.527) | -- | -- | -13.371 (14.211) |
| 6. + GDP per capita | -3.062 (12.827) | -8.235 (14.253) | 1.096 (15.879) | -2.367 (17.911) | -- | -- | -3.062 (12.827) |
| 7. Excl JPN & DEU | -14.482 (14.863) | -19.745 (15.646) | -29.930 (18.592) | 12.115 (17.586) | -- | -- | -14.482 (14.863) |
| 8. Predetermined (oadr+20) | -10.326*** (2.760) | -9.373*** (2.705) | -29.538*** (4.887) | 6.413 (4.285) | -- | -- | -10.326*** (2.760) |
| 9. Trilemma interaction | -4.419 (13.758) | -4.784 (14.455) | 8.496 (18.037) | 3.163 (9.239) | -- | -- | -4.419 (13.758) |

*Notes:*
- *Row 1: Baseline (Z_1,Z_2,Z_3 + controls). Reports Z_1.*
- *Row 2: Replace Z with old_dep, youth_dep, working_age_share. Reports old_dep.*
- *Row 3: 5-year lagged demographics. Reports Z_1_lag5.*
- *Row 4: First differences. Reports dZ_1.*
- *Row 5: Add gross_investment_gdp control. Reports Z_1.*
- *Row 6: Add gdp_pc_ppp control. Reports Z_1.*
- *Row 7: Exclude Japan and Germany. Reports Z_1.*
- *Row 8: Replace Z_1 with oadr_plus20 (predetermined). Reports oadr_plus20.*
- *Row 9: Add mi_index and Z_1*mi_index. Reports Z_1.*
- *Controls: rgdp_growth, output_gap, fiscal_bal_gdp, kaopen, nfa_gdp_lag.*